Certain cooktop appliances include gas burners for heating cooking utensils on the cooktop appliances. Gas burners generally include an orifice that directs a flow of gaseous fuel into a fuel chamber. Between the orifice and the fuel chamber, the gaseous fuel entrains air, and the gaseous fuel and air mix within the fuel chamber.
Consumers frequently prefer higher output gas burners in order to speed up cooking tasks. However, the gaseous fuel flow between the orifice and the fuel chamber has a practical limit with regards to available energy for mixing the gaseous fuel and air for clean combustion. One option to improve gas burner energy output is to add a fan to increase air flow into the fuel chamber relative to only entraining air with the gaseous fuel from the orifice.
Known gas burners with fans suffer several drawbacks. For example, the fans can be noisy. In a particular example, the gas burner described in U.S. Pat. No. 8,479,721 employs a variable speed fan that varies with a gas input in order to maintain proper fuel/air mixture throughout an operating range of the gas burner. The variable speed fan is costly and complex to operate. In addition, the gas burner is designed to operate with a high volume flow rate of fuel/air mixture and this inherently limits the gas burner's ability to operate efficiently with a low volume flow rate of fuel/air mixture. In another particular example, the gas burner described in U.S. Pat. No. 8,845,326 has a separate burner stage for lower outputs in the operating range of the gas burner. The separate burner stage requires a dual output valve which adds significant cost.
Accordingly, a gas burner with forced aeration that includes features for operating quietly over a majority of an operating range of the gas burner would be useful. In addition, a gas burner with forced aeration that does not require a variable speed fan in combination with fuel input across the operating range of the gas burner would be useful. Further, a gas burner with forced aeration that does not require a costly dual outlet control valve would be useful.